Phototelegraphy



May 13, 1930 v H. G. laARTr-{GLQ'MEW PHOTOTELEGRAPHY A Filed 0G13. 50, 1926 Patented May 13, 1930 UNITED STATES HAR@ Y GUY BARTHOLUME, @F LGNBK,

PHDTOTELEGRAE Application filed Dctober 3G, "i926, Serial No. llml, and. in Great Britain December 1'?, 1925.

My invention relates toa new and improved method ot j'ilioto-telegraphy and a new and improved apparatus tor this purpose.

@ne oi the objects ot my invention is to 5 provide a new and improved method whereby pictures can be recorded or sent by a. series of electric pulses, in which greater detail Will be secured.

Another object of my invention is to prolo vide .a method of telautography or phototelegraphy whereby a non-pictorialrecord will be formed or electrical pulses will be produced corresponding not only to spaced parallel rows of the small areas of the picture or the like which is to be recorded or transmitted, but also corresponding to the areas or lines ot the said picture Which are between the said spaced parallel rows.

Another object ot my invention is to pro- 513 vide for an improved reproduction ot the picture or the like which has been transmitted, or recorded in non-pictorial torni.

@ther objects of my invention are to produce improvements in that system or method H of photo-telegraphy or telautography disclosed. for example, in British ldatent No.

195.577?.r @ther objects ot my invention Will be set forth in the followinga description 'and draivings which illustrate a preferred embodiment thereof. it beingunderstood that the above general statement of the objects of my invention is intended merely to generally explain the same and not to limit it in any manner.

` Figs. L5 diagrammatically illustrate the progressive lateral variation of the reader points utilized in connection with my iniproved mcthod, 'from what, may be 'termed the standard position.I

Figs. (iv-'l0 illustrate what may be termed the longitudinal variation of said reader points from the standard position.

Fig. ll diagrammatically illustrates the relative locations ot the reader points.

Fig. l2 diagrammatically illustrates the/ improvement in the reproducingapparatus.

i3 diagrammatically illustrates the relative locations or" the shutter-controlled openinvs used in connection with the reproducing apparatus. rEhis is a section on the line 13,-13 of l2.

Fig. ldiagrammatically illustrates the light images formed upon the light sensitive 'film according to my nen7 and improved 55 method.

l5 illustrates the record tape.

The before mentioned British Patent lilo. 195,577. vell asA other patents, illustrate the Well known Bartlane process for making` non-pictorial records of pictures and tor transmitting pictures by lmeans of .phototelegraphy. According to this method, a series ot prints ot varying darkness are produced from a. picture by exposing said prints tor varying lengths of time to the action ot light. rence, one of these prints, vwhich may be called the first print, and which is exposed 'for the shortest period ot time, only records the brightest tones ot the picture to be reproduced, the second print records the tones of the irst print and in additioiiV the nent brightest tones, etc., until the last print records substantially all ot the tones of the picture to be transmitted. As stated in 'the said patent and as Well known to the art, these prints are formed upon a metal plate by means of a. iilm of hardened gelatin, vvhich acts as an efiicient insulator. Hence, when the said plate is connected to one 'terminal of a source ot electric current, and a metal point, which is called a readen is connected to the other terminal of the said source of current. and the reader `is moved A With/respect to the print in helical path, the circuit is ma de and broken as the reader passes over bare portions ot the plat-e and over portions of the said ilrn of insulating material.

'in order to secure perfect recording or transmission of the tone values ot a print, it Would be necessary tor the pitch of the said helical path to be equal to the Width or diameter of the reader point. This, however, is impossible tor anumber ot practical rea- /fsoiis, and in actual practice it has been Jfound necessary to impart a definite pitch to the said helical path so that the reader points do not pass over each and every consecutive This results in.

small area of each print.

noticeable loss of detail when the reader sponding smal-l areas of the respective prints,

which has been the practice up to the present time.

According to this invention, the reader points are placed so as to simultaneously contact with diiierent small areas ot the respective prints, these diii'erent small areas com: prisiiig a consecutive series.

For example, in Figs. 1-5, the five prints Y 1, 2, 3, e and 5 represent metal plates (preterably zinc plates) having the images of a picture in differenttone values reproduced thereon in films of insulating material. These prints 1-5 are depicted as planar, butl of course they couldbe bent around a revoluble cylinder in the well known manner. The reader points G, 7, 8, 9 and 10, instead of contacting with corresponding small areas of the said prints, contact with small areas which are arranged in what may he termed a diagonal series, the relative location of the said reader point-s being diagrammatically shown in Fig. 11. That is, the area of print t which at any given time is in contact with the reader point 9, is spaced from the corresponding area then in contact with the reader point 10, along a linev which is inclined to both edges of the said print Il, although it need not be necessarily a true diagonal.

On each of the prints, five imaginary parallel lines L are depicted and the pitch ot the relative movement between each reader point and its print is equalto tive times the distance between adjacent lines L. That is, if we assume'that the reader point 6 moves over the line L in one of its transverse movements, it moves over a line in the next transverse movement, which is spaced from line L5 by adistance equal to the distance between adjacent lines L.

Assuming that the reader point 10 contacts with the print 5 along the line L5, then the reader point 9 contactsv with the print l along the -line adjacent to L5, the reader point `8 is spaced for a distance equivalent to two lines,y

the `reader point 7 is spaced for a distance equivalent to three lines, and the reader point 5 is in contact with the line L. The diameter ,or width of a reader point is preferably very small, and much lessthan the distance between consecutive linesL. The respective lines are identified as L', L2, La, LL and L5.

If the line 11 shown in Fig. 1, for'example, has a width substantially equal tothe pitch of the path ot the reader points, then it' allthe reader points had 'the position or" point 6 shown in Fig. 1, the said points would iirst pass along the lines L and then along a line spacedfroni the line L5' without making contact with the narrow bar of insulating mate rial 1'1, so that this detail would be wholly lost. However, by having the iive'points in the position shown inFigs. 145, at least three Lacasse of such points pass over the `portions 11 of the prints so that at least some ot this detail is secured in the picture.

Ot course, if the portion 11 would correspond to the darkest tone which is being recorded, so that it would appear on only one I of the prints. it might be lost from the record or reproduction of the picture, but all areas corresponding to the lighter tones are passed over by two or more reader points so that some oi the detail which was formerly wholly lost is reproduced according to this improved method. rl`he portions 12 andlet of the respective prints illustrate the advantage of having the areas which are simultaneously in contacty with the reader points, laterallyspacing and the lateral spacing of the small Y areas of the prints which are simultaneously in contact with the reader points, but I prefer to make the longitudinal spacing greater than the lateral spacing.

I have not depicted in detail the record tape formed to provide a non-pictorial record of the picture, as this is well known in the art.

In order to properly reproduce the picture, the record tape T is caused to move behind a shutter member l5 which is provided with openings 16,1118. 19 and 20, arranged as shown in Fig. 13. Eachot the rows of holes T in the record tapeT controls the passage of light through one ot said light openings. rl`he light openings 16F2O inclusive may be regulated by means of independently movable shutters, so thatthe amount of light passed through 'each of the apertures 16-20,

when it is adjacent-a perforation of the tape T. canA be" suitably controlled.,

y(Parallel beams of light are caused to pass l through the holes in the record tape T, the light/being furnished by a suitable lamp 16 which'is associated with a lens system 17;

This part of the representation is wholly diagrammatic, as numerous lens systems for producing'a beam ot parallel rays ot light are well known. i f

The light openings iti-2O are focused upon but forni separate images which are so closely ``3` adjacent to each other that the e'ect upon the eye ol' the observer is the same though a single spot ol light had been Nfocused upon the image. 'llhat is, the tone ellects upon the reproduced picture are l'oiined by groups oit points or dots ol varying tone value. 'l`hes points or dots ol the original picture may be referred to :is elemental areas.

'llie British Patent lilo. ltli before inentioned as well as other patents upon the llartlane process illustrate mechanism whereby the circuits controlled by the live readers control live selector magnets, by :means of which one or moreor" a group of live punches can be selected to punch one or more (up to holes/l" in the tape rll. ln the. former patents illustrating the llartlane process the number oil holes in each roiv or group on the tape corresponded to the 'tone value or a single small area of tlie'picture. Un der the old method il it was desired to secure line detail, it ivas necessary to make the helical path of the reader means oi' si iall pitch. This would have required punching a very long` tape ivitli a resultant increase in the4 cost of transmission or reproduction ol 'thc tape. According to the improved method set forth herein, each row or group ol perforations Vl" corresponds to the tone value oi a series or group ol diderent small areas of the picture which is being reproduced so that much liner detail is secured Without increasing the length of the tape. ln reproduced pictures or the like which have been previously made by means of the llartlanel process as ivell as by other processes, each small area of the. reproduced picture correspondedio small area ol the plate used lior transmitting purposes. @n the contrary, and according` to the present invention, cach small area of the reproduced picture is a composite represen` tation o1? plurality or series ol closely ad- `iaceiit arcas oi the tranemittingplate or plates. Likewise, the perforated ,tape of the type shown in Fig. l5 and prepared. according topreviously known methods had a lateral grouper peilorations which corresponded to the tone'value ol a single small area of the picture or plate which was being transmitted. recording- 'to the present invention, a sinle llateral group of perlorations corresponds to a plurality of closely adjacent consecutive small areas of the pic-'ture or plate'thereol which is being' transmitted. i

lt is not always necessary to have the prints l-5 of varying' tone value, because il it is desired 'to transmit oi' record a signature or other black and White matter, said prints could have the same tone value. The improvedJ method enables the recording and transmitting ot signatures and 'the like ivith much greater detail and accuracy.

Kleitlier the neiv method set forth herein limited to the use of a plurality of prints ol picture, signature or the like. For example,

ii'a single print Were employed, the single reader point could be given a longitudinal movement along the line L, and it could then be given four lateral movements so as to consecutively touch the single print along the lines lagli The reader could thon be given a single longitudinal movement along' the line las and it could then be ,(iven lfour reverse lateral movements until it again contacted with the print along the line L'. That is, the single reader point could be moved along a path generally corresponding; to the helical path before mentioned, each intermittent series of movements along; this helical path being,y accompanied ivith intermittent lateral movements which are successively in opposite directions.

The single reader point could be used to control one of the rpunches at each of its positions so to securetlie result before mentioned` namely, to have each .row oi group or portez-ations on the tape correspond to the tone value el a series orgroup of areas on the picture, each area corresponding in size to that portion of the picture or print thereoil Whose tone value can be determined' by a single reader point.

Neither is my invention limited to the use or mechanical reader points or mechanical means in ,general for transforming; the tone value of the picture into electrical pulses, as my .invention would cover the use ot photo? electric readingA liiieans embodying the use of photo-electric' cells, selenium cells or the like. l has hitherto been known to rea d the picture either using' a singleprint or a pluralitjtv of prints) by causing the. reader means to move relatively to the print or prints along; a continuous helical line or lines, ivhile producing' groups or perforations. each groupo perlorations correspendingy to a group oi small areas which were continuously arranged along continuous line. According to this old method, the small areas ol successive groups ivere arranged alone; the same continuous line.` Assuming for convenience, that the picture to be read has an airis which for eiiainple, may be the` long edge thereof, the present method is distinguished from the old method in that the areas of successive ,grroups'are disposed in Zig-zag relationship:A

Hence much larger portion of the .picture is read because the respective groups of perlorations in tlie'tape correspond to successive groups ol small areas which are ar ranged in successive zigzag relation.

l have slioivn a preferred embodiment of.

my inventioii,-but it is clear that numerous changes and omissions couldbe made `Without departing from its spirit.

lltlherever have used the term perlorat ed tape, l Wish to include all surfaces upon. which markings or operations have been performed which cause portions of the said sur- Cai face to dille-r in light value or electrical value from the remainder thereof.

I claim zl. In the art of reproducing a picture, those steps which consist in simultaneously causing a series oi' reader means to co-operate with a plurality of prints of the said picture, the said reader'means being caused to simultaneously co-operate with different relative small areas of the respective prints, and combining the readings secured by said reader means to produce composite small areas on the reproduced picture.

, 2., In the art of reproducing a picture, those steps Which consist in simultaneously causing a series .of reader means to co-operate with a plurality of prints of the said picture., the said reader means being caused to simul taneously co-operate with different relative small areas of the respective prints, and conibining the readings secured by said reader means to produce composite small areas on .the reproduced picture, the said small areas of the prints forming a continuous series Whose ymembers are laterally spaced from each other.

3. In the art ofreproducing a picture, those steps Which consist insimultaneously cans! ing a series of reader means to co-operate With a plurality of prints of the said picture, the said reader means being caused to simultaneously co-oper-ate With -dirlerent relative small areas of the respective prints, and combining the readings secured by said reader means to produce composite small areas on the reproduced picture, thesaid small areas of the prints forming a continuous series Whose members are longitudinally spaced from each n other.

il. In the art of reproducing a picture, those steps Which consist in simultaneously causing a series of reader means to co-operatewith a plurality of prints of the said picture, the said reader means being caused to simulta* neously co-operate With dierentrelative small areas of the respective prints, and combining the readings secured by said reader means to produce composite small areas on the reproduced picture, the said small areas of the prints forming a continuous series whose members are laterally spaced from each other, the pitch of the path of the said reader means being substantially equal to the lateral distance between end members of the, said series. v

5. In the art of reproducing a picture, that step in the art Which consists in controlling the passage of light through a series bot light openings by passing in front of said light openings a tape having rows of perforations ea ch of which corresponds to the tone value of a diagonal series of successive small areas of a series of prints of the picture to be repr'c..luced, said series of small Aareas being' consecutively arranged in :zig-Zag` relation-- ship, the said light openings also forming a' diagonal series, and focusing the said light openings upon a sensitive film so that the images of said light openings are caused to form a unitary visual record.

6.` In the art ot reproducing a picture, that step in the art which consists in recording the tone values of groups of small areas ot the said 'picture by means of groupsof perforations on a tape, each group of said lperforations corresponding to a group of dii'lerent .small areas oi: the said picture. the successive groups of smallareas being arranged in' zig-Zag relationship. i

7. A perforated. non-pictorial record of a picture, said record having a plurality of groups ot' perfor-ations, the perforations in each group.corresponding respectively to thev tone rallies of a group of small areas of the said picture, the successive groups of small areas being arranged in Zig-Zag relationship.

In testimony whereof I alhx my signature.

HARRY GUY BARTHULOMEIV.

Cf: v

Qin

lno 

